基于多项式插值测速和LADRC的开关磁阻电机调速控制

Speed Control of Switched Reluctance Motor Using Polynomial InterpolationSpeedometer and LADRC

开关磁阻电机(SRM)时变非线性的特点使其精确的数学模型较难建立,当内外扰动较大时,传统PID控制器难以达到良好的控制性能。为了解决上述问题,采用线性自抗扰控制(LADRC)方法设计了SRM调速控制器。将非线性模型的不确定性和负载突然变化等合并作为一个总扰动,设计线性扩张状态观测器对扰动进行估计并进行补偿。采用二阶Lagrange插值多项式去逼近电机位置轨迹,从而计算得到瞬时速度,当电机进行导通角度控制时,依据瞬时速度估算转子位置进行控制。仿真对比表明,LADRC优于传统PID控制器。在DSP28335上对6/4 SRM进行了控制试验。结果表明,LADRC配合二阶Lagrange测速算法能较好地实现电机的提前开通和关断的角度位置控制。

Due to the time-varying nonlinear characteristic of switched reluctance motor(SRM),it is difficult to establish an accurate mathematical model.When the internal and external disturbances are large,the traditional PID controller cannot meet the requirement of high control performance.To solve these problems,a linear active disturbance rejection control(LADRC)method is used to design the speed controller of SRM.The uncertainty of the nonlinear model and the sudden change of load are synthesized as a total disturbance,and a linear extended state observer is designed to estimate and compensate the disturbance.A second-order Lagrange polynomial interpolation is used to approximate the position trajectory of SRM,thus the instantaneous speed can be calculated.The rotor position is estimated according to the instantaneous speed while SRM is operated under the conduction angular control mode.The simulation result shows that the LADRC controller is superior to the traditional PID controller.Finally,real-time control experiment of a 6/4 SRM is carried out using a DSP28335 board.The results show that the LADRC combined with the second-order Lagrange interpolation speedometer can realize the conduction angular control of SRM with early on/off operation.